Run Time Problems. When deploying a project on a server, you get the error "Could not load file or assembly 'Telerik.ReportViewer.WebForms' or one of its dependencies".

Environment

Product

Progress® Telerik® Reporting

Important

This article is related to the obsolete ASP.NET Web Forms Report Viewer. We strongly advice to Migrate to the HTML5 Viewer.

Description

When deploying a project with Telerik Reporting on a server, you get the following error:

"Could not load file or assembly 'Telerik.ReportViewer.WebForms, Version=x.x.x.x, Culture=neutral, PublicKeyToken=a9d7983dfcc261be' or one of its dependencies. The system cannot find the file specified"

Solution

During the installation of Telerik Reporting on a dev machine, the Telerik Reporting assemblies are added to GAC. When deploying a project using Visual Studio's built-in functionality, the assemblies from the GAC are not copied automatically, so you need to make sure the assemblies physically exist in the bin folder of your application. Full details are available in the Deploying Web Applications help article.